Vulcanization of elastomers with sulfur and a polyhaloaliphatic compound



United States Patent 3,317,440 VULCANIZATION 0F ELASTOMERS WITH SULFUR AND A POLYHALOALIPHATIC COMPOUND Peter E. Wei and John Rehner, Jr., Westfield, N.J., as-

signors to Esso Research and Engineering Company, a corporation of Delaware No Drawing. Ih'led Mar. 5, 1962, Ser. No. 177,179 28 Claims. (Cl. 260-) This invention relates to elastomeric polymers or copolymers vulcanized by sulfur and a polyhaloaliphatic compound, the present application being a continuation-inpart of SN. 147,047, filed Oct. 23, 1961, now abandoned.

It has heretofore been known to rvulcanize high un saturation rubbers, such as natural rubber, with sulfur and certain mild accelerators such as guanidine derivatives and thiazole derivatives. Low unsaturation rubbers have been vulcanized with somewhat greater difiiculty by the use of sulfur, zinc oxide and accelerators of greater activity, such as thiuram derivatives and dithiocarbamates.

By this invention it has been found that it is possible to formulate a vulcanizing mixture which will cure not only high unsaturation and low unsaturation elastomers but, surprisingly, elastomers of no unsaturation as well. More specifically, by the present invention, it has been found that elastomers and especially saturated elastomers may be cured with sulfur and a polyhaloaliphatic compound of the class consisting of polyhaloalkanes and polyhalocyclomonoalkenes. This is particularly surprising in view of the fact that sulfur in combination with polyhalocyclodiolefins will not cure many kinds of elastomers, such as saturated elastomeric polymers.

In particular, to 100 parts of elastomer is added between about 0.1 to parts by weight of sulfur, preferably 0.5 to 5 parts by weight, and about 0.2 to 30 .parts by weight of the polyhaloaliphatic compound, preferably 0.5 to 10 parts by weight. The resulting mixture is then heated to yield a vulcanizate. To further improve the process, zinc oxide, various fillers, and metallic accelerat-ors, such as FeC1 may be added to the mixture. Furthermore, improved results may also be obtained by masterbatching the polymer and the polyhaloaliphatic compounds of this invention prior to vulcanization.

The elastomers to which the present invention is applicable include high unsaturation rubbers such as natural rubber, polybutadiene, nitrile rubber (a copolymer of acrylonitrile and butadiene), SBR (a copolymer of styrene and butadiene), and polychloroprene (a homopolymer of 2-chloro-butadiene-1,3). The invention is also applicable to low unsaturation rubbers such as butyl rubber (a copolymer of a major portion of a C -C isoolefin with a minor portion of a C -C multiolefin), and chlorobutyl (chlorinated butyl rubber). Finally, and most surprisingly, elastomers of no unsaturation may be cured by the 3,317,440 Patented May 2, 1967 present invention. These elastomers include Vistanex (polyisobutylene) and the low pressure, substantially amorphous copolymers of ethylene and other alpha olefins. The copolymers thus include C to C alpha olefins such as propylene, l butene, and l-pentene. Propylene is particularly preferred as the other alpha olefin. The process for producing these low pressure copolymers is generally described in the literature, e.g., see U.K. Patent 856,736, Scientific American, September 1957, pages 98 et seq., and page 6 of copending application Serial No. 116,938, filed June 14, 1961. The invention is also applicable to C C alpha olefin homopolyme-rs such as polyethylene and polypropylene, to blends of various of the above listed elastomers, and to elastomeric copolymers containing more than two kinds of monomers, such as terpolymers and tetra-polymers. Finally it is to be noted that the use of mineral-filled or oil-extended rubbers will yield an improved vulcanizate.

The polyhaloaliphatic compounds which may be used in this invention include the polyhaloalkanes and the polyhalocyclom-onoalkenes. By polyhaloalkanes is meant C -C alkanes which have been substituted with halogen to such an extent that they contain not more than one hydrogen atom per molecule. Representative examples of these compounds include C01 CHCI hexachloroethane,

} heptachloropr-opane, octachloropropane, the bromine and iodine analogs of these compounds, and compounds of mixed halogenation such as dichloro-dibromomethane. Especially preferred are hexachloroethane, heptachloropropane, and octaehloropropane.

The polyhaloeyclomonoalkenes which may be used in this invention include cyclomonoolefins which contain between 3 and 20 ring carbon atoms and which have been substituted with halogen atoms'to such an extent that they contain not more than one hydrogen atom per molecule. Especially preferred of this group is octaehlorocyclopentene.

Other polyhaloaliphatic compounds which may be used include the C to C cycloalkanes which have been halogenated to such an extent that they include no more than 1 hydrogen atom per molecule.

It is desirable in this invention to further include zinc oxide in the vulcanization in an amount of from 0 to 20 parts per 100 parts of polymer.

Fillers are also desirable and a variety of carbon blacks, clays, silicas, and whitin-gs may be used. Best results are obtained with semi-reinforcing or highly reinforcing furnace and channel carbon blacks such as those designated commercially as SAF, SRF, HAF, EPC, and MPC types of carbon blacks. The amount of filler used can be from 0 to 200 parts by weight, but preferably 20 to parts per parts of elastomer is used.

The metallic accelerators which are useful in this invention include metals, inorganic metallic compounds,

the following tables the parts are by weight per 100 parts of elastomer.

and metallic salts of canboxylic acids. Preferred sub- 1 2 4 stances are aluminum powder, the metal halides, oxides, sulfides, ammonium sulfates and the metallic salts of alkyl EP Rubber, F 3616 100 100 e b monoand di-carboxylic acids. Especially preferred are gg ggfig gfifg? 28 50 iron oxide (ferrous and ferric), iron chloride, aluminum g g g 2 g hlor" 'r as iro 2-eth lhexoate an iron a at 5 5 1 on Oct 01 n y d Octachloropropane 5 5 5 5 dr-stearate. These substances may be present in amounts CURED PROPERTIES of about 0.0001 to 10 parts by weight, preferably 0.05 30725001? to 5 parts. These accelerators, it is to be noted, have Tensile,p.s.i 870 (Not ot Elong., Percent 100 cured) cured) surprisingly greater effectiveness when zmc oxide is absent 30/2g0 a Tensile, p.s.i 410 2, 640 (Not 1, 900 from the curing mlxture' Elong., Percent 680 680 cured) 730 The vulcanization of the elastomers may be effected gg g 500 3,480 (Not 2430 by thorough contacting of the elastomer with a curing 800 650 cured) 650 mixture, e.g., on a rubber mill, or in a Banbury mixer, ggfg g fig I e 0 an subiectlng the resultmg mixture to temperatures of Tensileypsj 970 3,830 110 2,750 250 to 450 F., preferably 280 to 400 F., for from 1 %9I g. ,Percent 800 580 900 600 to 180 minutes, preferably 1 to 90 minutes. Tensile, p.s.i 1,770 3,730 (Not 2,690 Elong., Percent 750 500 cured) 580 A more preferred method is to mix the elastomer and curing agent with or without sulfur or other additives in a masterbatch and then simply heat the resulting composition of matter to a vulcanizing temperature as needed (other additives may be mixed with the masterbatch just prior to heating). The advantages of producing the vulcanizate in this manner include the following: (1) mixing time is reduced, (2) the addition of the curing agent to the masterbatch lowers the Mooney viscosity of the mixture and thereby facilitates the processing of the elastomer.

EXAMPLE 2 Various inorganic metal salts were utilized as accelerators for the vulcanization of elastomeric ethylenepropylene copolymers with octachlorocyclopentene used as the vulcanizing agent. As can be seen from the following table, these agents are highly effective accelerators.

A B O D E F G EP Rubber, F-4734 100 100 100 100 100 100 100 EP Rubber, MD-460 HAF Carbon Black. 50 50 50 50 50 50 Sulfur 1 1 1 1 1 1 1 Zinc Oxide 2 2 2 2 2 2 2 Octachlorocyclopente 5 5 5 5 5 5 5 i nlgrganic Metal Salt None A101 FeCl FeCl fiHqo5 Sl'lC14-5HZ% ZIlClz CaClz Cure: minutes at 335 F.:

Tensile, p.s.i 310 2, 260 2, 360 2, 500 1, 750 1, 890 1, 500

Elongation, peree 900 550 350 480 650 780 650 H I J K L M N EP Rubber, F4734 l 100 EP Rubber, MD-460 b 100 100 100 100 100 HAF Carbon Black. 50 50 50 50 50 50 50 Sulfur 1 1 2 2 2 2 2 Zinc Oxide 2 2 2 2 2 2 2 Octachlorocyclopentene. 5 5 5 5 5 5 5 Inorganic Metal Salt... 13661221120 COClgfiHgO None FeCl AHZO HgClz AlBr F9NH4(SO4)2 PHR 5 5 5 5 5 5 Cure: 60 minutes at 335 F.

Tensile, p.s.i 1, 190 1, 000 360 2, 240 1, 720 1, 530 2, 000

Elongation, percent 780 580 1, 000+ 480 700 600 650 Ethylene-propylene copolymer, which contains 30 mole percent propylene units; inherent viscosity of 2.9 in decalin at C. b Ethylene-propylene copolymer, which has been deashed and contains Ethyl Antioxidant 702; contains 58% by mole of propylene units; uiherent viscosity of 3.93 in decalin at 135 C.

This invention and its advantages will be better understood by reference to the following examples.

EXAMPLE 1 The elastomeric ethylene-propylene copolymers were vulcanized with the use of octachloropropane. Details and results are given in the following table. In this and 75 EXAMPLE 3 Various organic metal salts are shown to be effective accelerators for the vulcanization of a rubbery ethylenepropylene copolymer with octachlorocyclopentene used as the vulcanizing agent. Details and results are as follows:

A B C D E F G EP Rubber, MD-460 e 100 100 100 100 100 100 100 HAF Carbon Black 50 50 50 50 50 50 50 Sulfur 2 2 2 2 2 2 2 Zmc Oxide 2 2 2 2 2 2 2 Octachlorocyclopentene 5 5 5 5 5 5 5 Organic Metal Salt None Iron Iron Iron Iron Iron Iron Naphthenate Octasol Distearate Nuolate Octoate Oxalate PHIL 5 5 6 6 5 5 Cure: 60 Minutes at 335 F.:

Tensile, p.s.i 360 2, 520 3, 000 3, 120 2, 160 2, 390 1, 950 Elongatlon, percent" 1, 000+ 600 700 650 680 550 570 Cure: 6 Minutes at 400 F Tensile, p.s.i 1, 200 2, 050 2, 930 2, 980 1, 790 2, 120 2, 240 Elongation, percent 980 500 750 600 580 550 500 H I J K L M N EP Rubber, MD-460 100 100 100 100 100 100 100 HAF Carbon Black 50 50 50 50 50 50 50 Sulfur 2 2 2 2 2 2 2 Zinc Oxide 2 2 2 2 2 2 2 Octachlorocyclopentene- 5 5 5 5 5 5 Organic Metal Salt Aluminum Aluminum Aluminum Cobalt Manganese Lead Cerium Stearate Octoate Lanrate Naphthenate Naphthenate Stearate Naphthenate PHR 5 5 5 5 5 5 Cure: 60 Minutes at 335 F.:

Tensile, p.s.i 2,080 850 1, 350 1, 440 590 1, 090 710 Elongation, percent 1, 000 850 950 780 1, 000 1, 000+ 1, 000+ Cure: 6 minutes at 400 F.:

Tensile, p.s.i 2, 400 2, 500 2, 590 1, 960 1, 960 2, 030 1, 880 Elongation, percent 700 580 650 650 650 950 750 Ethylene-propylene copolygner, which has been deashed and contains Ethyl Antioxidant 702; contains 58 mole percent propylene units; inherent viscosity of 3.93 in decalin at 135 EXAMPLE 4- The concentration eifect of ferric chloride, a typical accelerating agent, is shown in the following table:

l Ethylene-propylene rubber, which was (leashed and contained Ethyl 50 Antioxidant 702; contained 58 mole percent propylefinecunits with inherent viscosity of 4.26 as determined in decalin at 13 EXAMPLE Miscellaneous metal compounds as accelerators for oetachlorocyclopentene vulcanization are shown to be eifective in the following table. It is to be noted that these accelerators have a much greater effect when zinc oxide is absent from the curing mixture (compare run F with runs C or D).

, A B 0' D E F EP Rubber, MD-460 e 100 100 100 100 100 100 EP Rubber, F4723 None None None None None None HAF Carbon Black. 50 50 50 50 50 50 Sulfur 2 2 2 2 2 2 Zinc Oxide g Nong None Nong None 2 Octachloroc clo entene. Metal Comp bun zi None None Iron Oxidg Iron Oxidg None Iron Oxide HR. gall Oil 0 None None None 5 5 None Cure: mins. at 307 F.:

Tensile, p si 1, 500 2, 500 0 Elongation, per 750 700 0 Cure: 30 mins. at 320 F.:

Tensile, p s i 2, 870 2, 630 Elongation, per 500 580 100 Cure: mins. at 335 F.:

Tensile, p.s.i 360 2, 600 2, 690 1, 260 Elongation, percent 1, 000+ 350 600 350 950 See footnotes at end of table.

G H I .T K L EP Rubber, MD-460 m. 100 100 None None None None EP Rubber, F-4723 None None 100 100 100 100 HAF Carbon Black 50 50 50 50 50 50 Sulfur 2 2 1 1 1 1 Zinc Oxide 1 1 2 2 2 2 2 2 Octachlorocyclopenten 5 5 5 5 5 5 Metal Compound T102 SbrS5 None A1203 Aluminum Aluminum Isopropoxide powder PHR 5 5 5 5 Tall Oil None None None None None None Cure: 30 min Tensile, p s i Elongation, percent Cure: 30 mins. at 320 F.:

Tensile, p s i Elongation, percent Cure: 60 mins. at 335 F.:

Tensile, p.s.1 710 l, 060 310 810 1, 050 1, 050

Elongation, percent 1, 000+ 1,000 900 680 850 700 e Ethylene-propylene copoly'mer, which contains 50 mole percent propylene units with inherent viscosity of 3.93 and contains Ethyl Antioxidant 702 and has been deashed.

Contains no antioxidant and has 70 mole percent ethylene units in the rubber with inherent viscosity of 2.62 as determined in decalin at 135 C. and has not been deashed.

0 From Arizona Chemical Co. With trade name of Acintol FA #1, which contains less than 0.001% ash; 4% rosin acid; 4% unsaponifiables; 92% fatty acids (contains conjugated linoleic acid, 8% unconjugated linoleic acid, 36%; oleic acid, 50%; saturated acids, ASTM D803 tests=acid No. 191; saponification No. 195; Iodine No. 135; specific gravity, 0.9065.

cured.

EXAMPLE 6 In the following example the effect of various nonblack fillers is shown in the vulcanization of rubbery ethylene-propylene copolymers.

A B c D u er, 100 100 00 HiSil/233 5o E MPLE 7 eo 8X Sulfurma 2 2 2 2 35 The preparation and vulcanizatlon of compositions of Zinc Oxi c 2 2 2 2 Octachlorocyclopente 5 5 5 5 mattery comprising octachlorocyclopentene and ethylene- Fe(13lia (anshtydroisL- None 0.2 0.2 0.1 1 1 a c um eara e CureT: 1nmuteat335 3 200 3 960 1 980 2 620 propy ene copo ymers prepared by a solution process is ensi e, p.s.1 Elongation, percent 740 650 900 700 4 shown In the followmg table I PBoth of these rubbers were ethylene-propylene copolymers and had 58 mole percent propylene units in the rubber, but differed in inherent viscosity: B 3.93; b 4.26 as determined in deoalin at 135 C.

e A commercial rubber grade of finely divided silica, manufactured by the Columbia-Southern Corporation.

d A commercial rubber grade of finely divided kaolin sold by the 45 R. T. Vanderbilt Company.

A commercial rubber grade of finely dlvided silica sold by the Huber Corporation.

A B C D E Composition Synthesis:

(1) E1 Rubber Solution, F4723, g 500 500 500 500 500 (2) Octachlorocyclopentene, g 1 2 15 30 100 (3) Sodium Stearate, g 0.3 0. 3 0.3 0.3 0. 3 (4) Product, Dry Rubber, g 27.5 27.0 40.5 51.5 113.5 (5) Octachlorocyclopentene in Product (Based on amount used), Percent 3. 64 11. 11 37. 04 58. 25 88. 11 Analysis:

(6) Chlorine Found in Product, wt. Percent 2.61 6. 58 31. 17 39.85 62. 06 (7) Equivalent Octachlorocyclopentene,

wt. Percent 3. 16 7. 97 37. 48. 26 75. 15 Compounding: Composition, HAF Carbog Black, 50; Sulfur, 2; Zinc Oxide, 2:

30 minutes at 335 F.: Cure: 30 minutes at 335 F.:

ensile, p.s.i 190 440 2, Elongation, Percent 700 1, 000+ 280 Cure: 60 minutes at 335 Tensile, p.s.i 400 2, 690 1, 780 Elongation, Perce 1, 000+ 600 130 Cure: 60 minutes at 320 Tensile, p.s.i 470 2, 230 Elongation, Perce 1, 000+ 1,000+ 250 Cure: 6 minutes at 400 F..

Tensile, p.s.i 1, 520 2, 610 1, 730 Elongation, Percent- 900 300 100 Dilution of Composition with (8) Corresponding Composition, g 20 9.1 3. 2 (9) Pure EP Rubber, F4723, g 80 90.9 96.8 (10) Equivalent Octachlorocyclopentene (wt. percent) (7. 5) (4. 3) (2. 4)

See footnotes at end of table.

Compounding: Diluted Composition,

HAF Carbon Black, 50; Sulfur, 2;

Oxide, 2:

Cure: minutes at 335 F.:

Tensile, p.s.i.

100; Zine Elongation, Percent- Cure: 60 minutes at 335 F.:

Tensile, p.s.i-

Elongation, Percent- Cure: 60 minutes at 320 F.:

Tensile, p.s.i.

Elongation, Percent- Cure: 6 minutes at 400 F.:

Tensile, p.s.i-

Elongation, Percent.-

11 The rubber solution and oota-chlorocyclopentene were mixed thoroughly and then addedinto one liter of water at about 180 F. with stirring. This temperature was maintained until all the solvent had been practically stripped off so 'as to produce a workable rubber mass.

rubber mass was sheeted out and dried in air at room temperature.

b The EP rubber solution was a hexane solution of ethylenepropylene c'opolymer which con- 'tained 30 mole percent propylene units with an inherent viscosity of 2.4 as determined in decalin at 135" 0,

EXAMPLE 8 The following table indicates that the addition of octachlorocycl'opentene to ethylene-propylene rubber lowers the Mooney plasticity value of this composition of matter, thus rendering the product more readily processable in rubber manufacturing equipment.

Parts of octachlorocyclopentene mixed into 100 parts of ethylene-propylene rubber:

Mooney Plasticity (8 min/212 F.)

EXAMPLE 9 The following table indicates the effectiveness of octa- The wit-h hexachl-oroethane. lows propylene of Example 9 are shown to be vulcanizable Details and results are as fol- A B C D E Polyethylene B 100 100 100 None None Polypropylene None None None 100 100 HAF Carbon Black. 50 50 50 50 Sulfur 0 1 1 1 1 Zinc Oxide 0 2 2 2 2 Hexachloroethane. 0 0 10 0 5 Cure: 30 mins. at 320 F.

Tensile, p.s.i 1, 820 2,000 1, 950 0 1, 470

Elongation, percent- 100 180 0 150 Cure: 30 mins. at 33 Tensile, p.s.i 1, 790 1, 850 1, 950 780 2, 060

Elongatmn, percent. l00 200 0 550 Cure: 60 mins. at 33 F.:

Tensile, p.s.i 1, 770 1, 960 1,950 700 2, 280

Elongation, percent. 100 180 100 150 550 Gel Content, percent 27 25 97 24. 4

Bakelite Polyethylene (DYNH-3)mixed on rubber mill at 200 F.

Amorphous, M.W.: 270 000 chlorocyclopentene 1n vulcamzmg high pressure poly- 50 ethylene and amorphous polypropylene. residue aft r drying A B C D E F Polyethylene 100 100 100 None None None Polypropylene b None None None 100 100 100 HAF Carbon Black 50 50 v 50 50 50 60 Sulfur 0 1 1 1 l 1 Zinc Oxide O 2 2 2 2 2 O otachlorooyclop entene.- 0 0 10 0 3 10 Cure: 30 mins. at 320 F.:

Tensile, p.s.i 2, 000 2, 190 Elongation, percent l00 200 Cure: 30 mins. at 335 F.: r

Tensile, p.s.i l, 790 1, 850 2, 270 780 1, 820 1, 950 Elongation, percent. 200 0 580 600 Cure: 60 mins. at 335 F.:

Tensile, p.s.i 2, 500 700 2, 2, 780 Elongation, percent-.. 150 500 450 Gel Content, percent 0 25 100 24. 4 49. 0 74. 3

Bakelite Polyethylene (D yNn-wnixed n rubber mill at 200 F.

b Amorphous; molecular weight 27 through a 325 mesh screen and weighing the insoluble residue after drying.

e No cure. e No sample.

Determined by heating in decalin at 135 C. at 0.1% cone. for one hour, and then filtering through a 325 mesh screen and Weighing the insoluble EXAMPLE 11 In the following table, it is shown that octac-hlorocyclopentene will efiectively vulcanize unsaturated rubbers such as the butyl-SBR blends:

A B C D E F G H I 1 Butyl 218 100 75 50 None 100 75 50 25 None SB R 1500 b None 25 50 75 100 None 25 50 75 100 HAF Carbon Black- 50 50 50 50 50 50 50 50 50 50 Sulfur 2 2 2 2 2 2 2 2 2 2 O ctachlorocyclopent None None None None None 5 5 5 5 5 Cure: Mins. at 320 F Tensile, p.s.i. 530 260 170 130 110 700 480 1, 000 2, 250 2, 480 Elongation, percent 1,000+ 600 650 700 600 630 400 250 330 450 Cure: 60 Mins. at 335 F.:

Tensile, p.s.i 280 470 1, 160 2, 140 3, 000 2, 090 790 1, 980 2, 190 2, 750 Elongation, percent 1, 000+ 400 280 380 550 430 150 100 150 200 a A commercial grade of butyl rubber (an isobutylene-isoprene copolymer produced by the Enjay Chemical Company). b A commercial type of butadiene-styrene copolymer.

EXAMPLE 12 In the following table, it is shown that octachlorocyclopentene is also useful for vulcanizing blends of butyl rubber with other rubbers.

A B C D E F Butyl 218, g. 100 100 100. V 75 75 50. Other rubber S5moked Sheet 2ssmoked Sheet Sanoked Sheet. G 2 5 HAF Carbon Black 50. 50 50 50 50.. 50. Sulfur 2 2 2.. 2 2. Zinc Oxide 2 2 2 .2 2. Octachlorocyclopentene 5 2 H 5. Cure: 30 min. at 320 F.:

Tensile. p.s.i 530 700-- 1,910- 280 670 1,280. Elongation, Percent 100+ 630-- 600 500 280 200. Cure: 30 min. at 335 F.:

Tensile, p s i 2,700.- 350 560 1,090. Elongation, Percent 530 70 250 200. Cure: 60 min. at 335 F.:

Tensile, p.s.i 280 2,090- Elongation, Percent 1,000+ 430 G H I J K L M Butyl 218, g. 75 75 75-" 75 75 75. Other Rubber Hypalon Hypalon 40 ole-4 polycis-4 poly- Paracril C Paracril 'C Neoprene W. l

butadiene. butadiene. G- -2-" 25 25 25 25 25 25 50. HAF Carbon Black 50 50 50 50 50 50. Sulfur 2 2 2 2 2 2 2, Zinc Oxide 2 2 2 2 2 2 2. Octachloroeyclopentene 2 2 2 '2. Cure: 30 min. at 320 F.:

Tensile, p.s.i 580 570 290-- 870 770 1,000- 1,660. Elongation, percent 50 50 330 230 430 230 130. Cure: 30 min. at 335 F.:

Tensile, p.s.i 440 670 40 820 830 1,110-" 1,480. Elongation, percent 0 0 400 150 250 13 100. Cute: min. at 335 F.:

Tensile, p.s.i Elongation, percent a A commercial grade of butyl rubber (an isobutylene-isoprene copolymer produced by the Enjay Chemical Company).

b A chlorosulfonated polyethylene (E. I. DuPont de Nemours Compan a A commercial poly-cis 1,4-butadiene (Phillips Chemical Company).

EXAMPLE 13 In the following table, it is shown that chlorinated parafiin wax is not a vulcanizing 'agent for ethylenepropylene rubbery copolymers:

a 49 mole percent propylene units.

mined in decalin at 135 C.

paraffin wax.

(Catalyst=VC1a/Al(CaH1a)a)- b Diamond Alkali Company Chlorowax -a resinous chlorinated Inherent viscosity of 5.7 as deter- A commercial copolymer of butadiene and acrylonitrile (United States Rubber Company) B A commercial polychloroprene (E. I. DuPont de Nemours Company).

In the following t EXAMPLE 14 able, it is vshown that perhalocyclopolyenesare not effective vulcanizing agents for ethylenepropylene rubber.

A B C EP Rubber, F-3616 100 100 HAF Carbon Black 50 50 50 Sulfur 1 1 1 Zinc Oxide 2 2 2 Perhalocyclopolyene None b 10 s 10 Cure: 30 minutes at 280 F.:

Tensile, p.s.i 370 660 470 Elongation, percent 600 600 780 Cure: 30 minutes at 320 F.:

Tensile, p.s.i 450 520 600 Elongation, percent 630 550 750 Cure: 60 minutes at 335 F.:

Tensile, p.s.i 410 650 500 Elongation, percent 580 450 730 Ethylene-propylene rubber, which contains about 49 mole percent propylene units and has an inherent viscosity of 5.7 as determined in decalin at 0.; prepared with VC1a/Al(CtH 3)3 complex catalyst.

' Hexachlorocyclopentadiene.

v Hexachlorob enzene 7 ,EXAMPLE 15 In the following table, it is shown that perhaloalkenes are not effective vulcanizingagents for ethylene-propylene rubber:

2. A curable composition of matter comprising a saturated elastomer, sulfur, and a polyhaloalkane having no more than one hydrogen atom.

3. The composition of claim 2 wherein the polyhaloalkane contains from 1 to 20 carbon atoms, and the halogen is selected from the class consisting of chlorine, bromine and iodine.

4. The composition of claim 3 which additionally contains an accelerator selected from the class consisting of aluminum powder, inorganic metal compounds, and metallic salts of ca-rboxylic acids.

5. The composition of claim 4 which additionally contains about 1 to 200 parts of filler per 100 parts of elasto- 6. The composition of claim 5 which additionally contains about 1 to 20 parts of zinc oxide per 100 parts of 7. The composition of claim 6 wherein the elastomer is an ethylene-propylene copolymer.

8. The composition of claim 7 wherein the polyhaloalkane is hexachlorethane.

9. The composition of claim 7 wherein the polyhaloalkane is.octachloropropane.

10. A cured composition of matter comprising a saturated elastomer sulfur and a C -C polyhaloalkane containing no more than one hydrogen atom.

11. The cured composition of claim 10 wherein the halogen of the polyhaloalkane is selected from the class consisting of chlorine, bromine, and iodine.

12. A curable composition of matter comprising an A B C D E EP Rubber, F-36l6 1 100 100 100 100 100 HAF Carbon Black..- 50 50 50 50 50 Sulfur 1 1 1 1 1 Zinc 0xide 2 2 2 2 2 10 Perhaloalkene a b c d PHR 10 10 10 10 Cure: 30 mins. at 280 F.;

Tensile, p.s.i 370 650 520 550 480 Elongation, percent 600 750 650 700 650 Cure: 30 mins. at 320 F.:

' Tensile, p.s.i 450 660 630 600 330 Elongation, percent I 630 780 400 750 650 Cure: 60 mins. at 335 F.:

Tensile, p.s.i 410 700 390 550 530 elastomer. Elongation, percent 580 650 230 650 730 Ethylene-propylene rubber, which contains about 49 mole perce n V propylene units and has an inherent viscosity of 5.7 as determined in decalin at 135 0.; prepared with vC13/A1(CflH13)3 complex catalyst.

a Tetrabromoethylene. Y b Hexachloi'opropene. c 1,1,2-trichloroo,3,3-trifiuoropropene. d Hexachlorobutadiene.

EXAMPLE 16 In the following table, the effect of the number of hydrogen atoms in the polyhaloahphatic molecule on the vulcanization of ethylene-propylene rubber 18 shown. As can be seen, only those molecules with no more than one hydrogen atom are effective.

A B G D E F G F-3616 EP Rubber 100 100 100 CP2 EP Rubber HAF Carbon Black 50 50 Sulfur 1 1 1 Zinc Oxide 2 2 2 Polyhaloaliphatre. None a b HR None 10 10 Cure: 30 minutes at 280 F.:

Tensile, p.s.i 370 630 630 Elongation, Percent 600 650 750 Cure: 30 minutes at 320 F.:

Tensile, p.s.i 450 1,030 470 Elongation, Percent 630 450 600 Cure: 60 minutes at 335 F.:

Tensile, p.s.i 410 1,050 900 Elongation, Percent 580 450 600 l Ethylene-propylene rubber, which contains about 49 has an inherent viscosity of 5.7 as determined in decalm e ia)s complex catalyst.

mole percent propylene units and at 135 0.; prepared with V01 2 Ethylene-propylene rubber which contains about 37 mole percent propylene units and 0.; prepared with V01 One Hydrogen: a. Iodofonn; b. Pentabromoethane; e. 1, ,1,2,2,3,3-heptachloropropane.

B. Two Hydrogens: d. 1,1,2,2-tetraehloroethane. 0. Six Hydrogens: e. 13,3,4,5,o-hexachlorocyclohexane.

The advantages of this invention will be apparent to those skilled in the art. Cured elastomers are provided of high tensile strength, having substantially no odor, and with satisfactory physical characteristics. The vulcanizing agents herein disclosed have been found'to cure not only unsaturated elastomers but also elastomers having no unsaturation at all. I

This invention has been described in connection with certain specific embodiments thereof; however, it should be understood that these are by way of example rather than by way of limitation and it is not intended that the invention be restricted thereby.

What is claimed is:

1. A curable composition of matter comprising an elastomer, sulfur, and about 0.2 to 30 parts per 10 0 parts elastomer by weight of a polyhaloaliphatic compound having no more than one hydrogen atom selected from the class consisting of poly-haloalkanes and polyhalocyolomonoalkenes containing 3 to 20 ring carbon atoms, said elas-tomer being saturated when polyhaloa'lkanes are utilized.

elastomer, sulfur, and a polyhalocyclomonalkene having 3 -to 20 ring carbon atoms containing no more than one hydrogen atom. I

13. The composition of claim 12 wherein the polyhalocyclomonoalkene contains from 3 to 20 ring carbon atoms andthe halogen is selected from the class consisting of chlorine, bromine and iodine.

14. The composition of claim 13 which additionally contains an accelerator selected from the class consisting of aluminum powder, inorganic metal compounds and metallic salts of carboxylic acids.

15. The composition of claim 14 which additionally contains about 1 to 200 parts of filler per 100 parts of elastomer.

16. The composition of claim 15 which additionally contains about 1 to 20 parts of zinc oxide per 100 parts elastomer.

17. The composition of claim 16 wherein the elastomer is an ethylene-propylene copolymer.

cyclomonoalkene is octachlorocyclopcntene.

19. A cured composition of matter comprising an elastomer, sulfur and a polyhalocyclomonoalkene containing from 3 to 20 ring carbon atoms and no more than one hydrogen atom.

20. The cured composition of claim 19 which additionally contains an accelerator selected from the class consisting of aluminum powder, inorganic compounds, and metallic salts of carboxylic acids.

21. A curable composition of matter comprising substantially amorphous polypropylene, sulfur, and octachlorocyclopentene.

22. A curable composition of matter comprising octachlorocyclopentene, sulfur, and a blend of a copolymer of a major portion of a C C- isoolefin with a minor portion of a C C multiolefin, and a second rubber.

23. The composition of claim 22 wherein said second rubber is natural rubber.

24. The composition of claim 22 wherein said second rubber is a butadiene-styrene copolymer.

25. The process of curing an elastomer which comprises mixing said elastomer with sulfur and a C -C polyhalocyclomonoalkene having no more than one hydrogen atom, and heating to a vulcanizing temperature.

26. The process of claim 25 wherein the polyhalocyclomonoalkene is octachlorocyclopentene.

27. The process of curing a saturated elastomer which comprises mixing said saturated elastomer with sulfur and a C -C polyhaloalkane having no more thanone hydrogen atom, and heating to a vulcanizin'g temperature.

28. The process of claim 27 wherein thepolyhaloalkane is hexachloroethane.

References Cited by the Examiner MURRAY TILLMAN, Primary Examiner.

WILLIAM H. SHORT, LEON J. BERCOVITZ, M. J.

TULLY, K. B. OLARKE, J. W. SANN-ER,

Assistant Examiners. 

1. A CURABLE COMPOSITION OF MATTER COMPRISING AN ELASTOMER, SULFUR, AND ABOUT 0.2 TO 30 PARTS PER 100 PARTS ELASTOMER BY WEIGHT OF A POLYHALOALIPHATIC COMPOUND HAVING NO MORE THAN ONE HYDROGEN ATOM SELECTED FROM THE CLASS CONSISTING OF POLYHALOALKANES AND POLYHALOCYCLOMONOALKENES CONTAINING 3 TO 20 RING CARBON ATOMS, SAID ELASTOMER BEING SATURATED WHEN POLYHALOALKANES ARE UTILIZED. 